# Conte o número de
db.wx_user_info.find () count () .;
#Criação em lote
var arr = [];
para (var i = 1; i <= 2; i ++) {\ ", \" groupid \ ": 0, \" tagid_list \ ": []}"});
}
db.wx_user_info.insert (arr);
# 修改
para (var i = 2; i> = 1; i -) { db.wx_user_info.update ({"nickName": i}, {"$ set": {"nickName": i + 1}}) }
# 删除
para (var i = 2; i> = 1; i -) { db.wx_user_info.remove ({"nickName": i}) }
#Single query db.getCollection ('wx_user_info'). Find ({nickName: 2.0})
#Reverse query db.dx_user_info.find (). Sort ({"nickName", "$ i"})